| 摘要: | 摩擦係數為斷層帶和山崩滑動面中重要之力學特性，其控制著斷層之剪動行為也決定山崩的運動過程，然而，摩擦係數與行為受到剪動速度、位移、正向應力、水、溫度、礦物組成、粒徑大小與剪切構造發育程度等影響。藉由低至高速旋剪設備進行不同速度之長位移旋剪實驗，將實驗結果建立速度相依摩擦律，便可計算摩擦係數於不同的滑移速度與累積位移之變化，若考慮其他不同實驗條件進行量測與分析，便可將其納入摩擦律中評估所造成之影響，並描述該材料所組成滑動面於滑動不同階段時之剪切強度。本論文將介紹引入速度位移相依摩擦律之Newmark 位移法來計算地震誘發山崩塊體之運動過程，以集集地震誘發之草嶺山崩為例，成功地再現草嶺山崩啟動、加速、撞擊與停止之運動歷程；另一方面，在非線性臨界楔模型中，透過地表調查與地層剖面分析，推估臨界楔之強度，再利用斷層泥於不同速度(長位移)進行旋剪摩擦實驗，建立大範圍速度與摩擦係數關係，評估適當之基底滑脫面摩擦係數。本論文證明速度位移相依摩擦律不僅可應用於地震誘發之高速山崩，亦可應用於大地構造空間與時間尺度之模型中。;The friction coefficient of a fault gouge or sliding plane dominates the fault dynamics and kinematics of a landslide. However, the friction coefficient and behavior of fault gouges or sliding planes are influenced by the slip rate, displacement, normal stress, pore pressure, water content, temperature, mineral content, particle size, and shear structure. We performed a series of rotary shear tests under different experimental conditions from low to high velocity to establish the velocity-dependent friction law. Accordingly, the friction coefficient can be evaluated by varying the slip rate and accumulated slip displacement. This study presents two applications of the velocity-dependent friction law, a kinematic analysis of catastrophic planar failure and an estimation of the strength of the detachment fault of the accretionary wedge. The first target is the famous planar failure of Tsaoling landslide, Taiwan, which was triggered by the 1999 Chi-Chi earthquake. We adopted Newmark displacement analysis with velocity-displacement dependent friction law to reproduce the kinematic history of the Tsaoling landslide, considering the phases of initiation, acceleration, collision, and deposition. For the second application, we present a modified critical taper model with nonlinear Hoek-Brown failure criterion and utilize field investigations and laboratory tests to estimate the wedge strength in western central Taiwan. The slip velocity dependent friction coefficient of the detachment fault can be obtained via a series of rotary shear tests with a wide slip rate range. Consequently, the rotary shear test and velocity-dependent friction law can be applied successfully to quantify the kinematics of the catastrophic landslide and the critical taper angle of accretionary wedge, even as their temporal and spatial scales are extremely different. |
